I am running a VPN server on my old windows XP machine so that a few others can securely get into my network. Connecting to the server locally works perfectly and there are no issues however when I try and access it from the internet even after port forwarding 1723 I still cannot get access.. I have attached a screenshot of the error i get if someone is able to assist me with fixing this issue..
Based upon the information provided so far in your post, this link may prove helpful-->
Not really enough detail here
I assume that the Port is OPEN also from the REMOTE machines. Some Internet providers now block almost all ports so you might need to "Get around" by using standard Open ports - usually 80 / 8080 that have to be open for web access.
Perhaps using something like Putty would work better. This would then Tunnel using standard Ports which are usually open anywhere.
Need more info on your set up